Monday, February 25, 2008

Milking Roger Clemens

Due to reasons that are largely irrelevant to this blog, I've had some time on my hands recently. It probably says something really bad about me, but I've spent my lunches watching C-SPAN lately. If you've been following the news over the last couple of weeks, you know that baseball player Roger Clemens has been accused of using performance enhancing drugs including human growth hormone. Since this isn't a legal or sports blog, it's not really relevant to Pint and Fork whether he did or did not use HGH contrary to MLB regulations, US law, and his own health.

When I was watching the other day, some doctor said something I found incredibly interesting. He said that detecting abuse of HGH poses an extremely difficult analytical challenge because it's literally the same hormone that is present in every single human. So to determine abuse, laboratory analysis requires looking at sharp changes in HGH levels over time. The problem with that is that players are not tested often enough to do that typically, and that somatic HGH levels covariate with dietary and other environmental factors.

En passant, he suggested that the US government could require all HGH chemical formulation to contain an inert chemical tracer. That is, a chemical that has no physiological, medicinal, or any other business being in the human body that doesn't help or harm it in any way. Preferably, it would be something that would persist in the body for some time after receiving a dose of HGH.

Now, do understand that I have no idea what a suitable tracer chemical would be. But I have a feeling that there are smart people in this world who would be able to figure out just that kind of problem.

However, if the government required that an inert tracer were included in rBGH we would be able to solve that problem.

But please bear with me as I go into a little more detail.

The use of rBGH (also known as bovine somatotropin or bST) was made possible by Monsanto in the early 1980s. It was quickly shown to increase milk production in cows by ten to twenty percent, and due to industry pressure was approved by the FDA for use in 1993. The FDA's short-sighted "science-based approach" to such matters also contributed to the relatively rapid approval of rBGH. At any rate, the FDA reviewed 130 industry-funded studies that involved testing 21,000 cows and determined that rBGH was safe for human consumption and does not affect human health (i.e. it doesn't stimulate human growth).

Two problems. First, cows that are treated with rBGH develop mastitis more frequently than non-rBGH treated cows. This requires the extensive use of antibiotics, which are positively known to enter the milk of treated animals. The FDA has a mandate to test for antibiotics in milk, but in practice it does not even come close to having the resources to do so.

Second, the use of rBGH increases levels of insulin-like growth factor-1 (IGF-1). Unlike rBGH which is a different chemical entirely from HGH and therefore has no biological activity, bovine-derived IGF-1 is chemically identical to human IGF-1. And IGF-1 may well stimulate unnatural growth in infancy and may increase the risk of cancer for adults. This risk is mitigated somewhat by the denaturation (biologically deactivated for non-chemists) of the protein in gastric fluid, however some has been demonstrated to be absorbed before it can become denatured.

Anyway because rBGH is chemically indistinguishable from natural BGH the FDA determined that it's illegal to label dairy products as being rBGH free. I personally think that given the two risks noted above, I -- as the consumer -- should be given the ability to make a choice. And I can't make a choice without adequate labeling. But, hey, maybe that's just me.

The relevant FDA guidance document discusses this matter explicitly. It says that

FDA is concerned that the term ``rbST free'' may imply a compositionaldifference between milk from treated and untreated cows rather than adifference in the way the milk is produced.

So you can't label milk as "rBST free" unless you provide what the FDA considers "proper context":

FDA believes such misleading implications could best be avoided by theuse of accompanying information that puts the statement in a propercontext. Proper context could be achieved in a number of differentways. For example, accompanying the statement ``from cows not treatedwith rbST'' with the statement that ``No significant difference hasbeen shown between milk derived from rbST-treated and non-rbST-treatedcows'' would put the claim in proper context. Proper context could alsobe achieved by conveying the firm's reasons (other than safety or quality)for choosing not to use milk from cows treated with rbST, as long asthe label is truthful and nonmisleading.(Bold type added by Pint and Fork for emphasis.)

In other words, you can give your reasons for not using rBGH right on the package, as long as it doesn't imply that your product is safer (as good science has shown) or is of higher quality (which is common sense to this observer).

So clearly, an FDA-mandated inclusion of an inert tracer in rBGH formulations could overcome this hurdle with a techno fix. That is to say, with the least amount of effort because it requires no changes in the way things are done. But some facts, I think, undercut the need for rBGH in the first place.

First of all, it cannot be argued that American farmers need rBGH to keep pace with foreign demands. For one thing, milk is fresh only briefly and it cannot be effectively frozen. rBGH has been banned in the European Union, Canada, Australia, New Zealand, and Japan. So at first glance, it would seem that we could increase the sell-ability of US milk if we rendered rBGH illegal because then we could sell it in Canada.

Second, there has always been a surplus of milk -- even during the Great Depression. There is no reason why we would want to produce more of it. In fact, more of a product will devalue the commercial value of that product and hurt the small-scale operations the most.

Third, there are a finite number of antibiotics in our pharmacopoeia. We should be trying to limit their use to the greatest extent possible for only cases where the need is warranted. The use of antibiotics in cattle for meat production has been demonstrated to lead to an increase of antibiotic resistant pathogens. This is a very bad thing. If we can reduce the use of antibiotics by not using rBGH, then so much the better.

Fourth, the FDA itself opened up the door of certification programs. That is, a third party could conduct regular inspections and audit paper records to verify that rBGH was not used in raising cows. In an FDA interim guidance document on the subject, they clarify that this can be done not to address safety concerns but to defend the farmer against claims that the label is misleading. To quote the FDA document:

States should consider requiring that firms that use statements indicatingthat their product is ``certified'' as not from cowstreated with rbST beparticipants in a third party certification program to verify that the cowshave not been injected with rbST. States could seek to ensure thatcertification programs contain thefollowing elements: Participating dairyherds should consist of animals that have not been supplemented with rbST.The program should be able to track each cow in the herd over time. Milkfrom non-rbST herds should be kept separate from other milk by a physicalsegregation, verifiable by a valid paper trail, throughout the transportationand processing steps until the finished milk or dairy product is in finalpackaged form in a labeled container. The physical handling and recordkeepingprovisions of such a program would be necessary not because of any safetyconcerns about milk from treated cows but to ensure that the labeling ofthe milk is not false or misleading.

Unfortunately, farmers are very rarely responsible for the distribution of their product. That means that physically separating certified rBGH free milk on the way to the packaging facility is often impossible as a matter of practice.

At any rate, there is the kind of technical fix the food industry so much adores in the form of inert tracers. This completely invalidates the argument that dairy products cannot be labeled "rBGH free" because there's no chemical difference. With this in mind, the FDA should revisit their guidance document and allow such designations to be included.

4 comments:

Davis
said...

One solution would be to find a protein which is expressed only upon increased growth hormone levels, and measure amounts of that protein.Apparently one of the steroid suppliers is working here in Champaign right now.

My grandparents are dairy farmers who oppose the use of rBGH mostly because it's bad for the cows.

I do have to note though that even though the FDA probably does not test much milk for antibiotics, many (most?) reputable dairies will.

This is how it works for my grandparents that sell their milk to Prairie Farms (IL). The milk truck comes 2-3x a week to pick up the milk that's stored in their huge refrigerated tanks. The night before the truck comes they take a sample of the milk and run a test to see if there is any drug residue or bacterial contamination. If there is (extremely rare, because when a cow is being treated with antibiotics they mark her and do not put her milk into the system) they call off the truck. If they wouldn't catch the problem or be dishonest, this is what would happen:

When the truck comes, the driver takes a sample of the milk, then puts the rest in his truck. S/he picks up everyone's milk in a certain area, making sure to get a sample of each one. Then s/he takes the milk to the plant. Before the milk can be taken off the truck, the pooled milk in the truck is tested again by Prairie farms. This time, if the milk has problems (I'm not sure of everything they look for), the whole truck is dumped down the drain. Then they test the individual farm's milk samples, and whoever caused the contamination/drugs/whatever has to PAY for the entire truck of milk.

I'm not saying the dairy industry is perfect, but if you get to know a particular brand I'm sure they'd be happy to tell you how they test their milk, and I bet you'd find a lot more goes into it than you think. Yes, some dairies accept rBGH milk, but some pledge not to and most will screen every batch of milk they sell for antibiotic residue.

Kate, thank you for reading my post and taking the time to provide such a thoughtful and detailed response.

Regardless of whether some dairies actually have milk free of rBGH and whether milk has no significant concentration of antibiotics, I feel that consumers should be informed as to whether milk comes from a source that uses rBGH or one that does not. The FDA has a policy of not allowing such label claims to be made, based on the fact that the use of rBGH doesn't represent a compositional difference in milk or represent an obvious safety hazard. The use of rBGH may not be safe for the reasons stated in the post, and has far-reaching consequences outside of mere safety considerations.

I hoped to show in this post that there are ways to analytically test for the presence of rBGH, thus overcoming the FDA's objection.